This invention relates to vehicle height adjusting devices of the kind including a source of pressurized air, and an elevating device receiving the pressurized air from the source for elevating or lowering a body of a vehicle.
Conventionally, a drain separator or a dehumidifying or dehydrating device is disposed between the source of pressurized air and the elevating device so as to prevent the elevating device from the accumulation of water which would impair the operational characteristics of the elevating device and induce corrosion.
One previous drain separator contains therein a desiccant such as silica gel or the like whereby the water in the pressurized air is absorbed by the desiccant. The drain separator is simple in construction and compact in size. In elevating the height of the vehicle, the pressurized air is supplied from the source, through the drain separator, to the elevating device. In descending or lowering the vehicle body, a portion of the pressurized air in the elevating device is released to the atmosphere. For selectively connecting the elevating device with the atmosphere, a switching valve is connected to the drain separator such that the pressurized air in the elevating device is released to the atmosphere through the drain separator, whereby a portion of water absorbed in the desiccant will be released therefrom and the dehydrating power of the desiccant will partly be restored.
However, the dehydrating power of the desiccant cannot essentially be restored by simply reciprocating the air and it has been required to exchange or replace the desiccant at a predetermined time interval. Further, there is another problem in that the desiccant will dissolve into powder which will be carried to valves, pipings or the like, thereby clogging them.